The purpose of the proposed research is to investigate learning mechanisms. Learning is an important form of behavioral adaptation based on past experience. A cornerstone of psychological research on learning in the twentieth century has been the assumption that learning mechanisms are similar across species and situations. For example, this assumption has provided the foundation for much of the research on the neurobiological bases of learning. Encouraged by the assumption of generality, investigations of learning have been limited to a few model systems. In most behavioral research on animal learning, for example, the subjects are motivated by hunger or thirst, or by fear. The proposed research will test the generality of learning mechanisms by investigating learning in a markedly different response system, reproductive behavior. In addition to providing information about the generality of learning mechanisms, the research may lead to the discovery of adaptive specializations of learning and may provide information that will be useful in the development of animal models of sexual dysfunction. Because the experiments require controlling and manipulating the sexual history of the subjects, the research will be conducted with animals raised specifically for the purpose. Japanese quail, a domesticated poultry especially well suited to laboratory research on sexual behavior, will be used. One set of experiments will be devoted to exploring how learning is involved in sexual behavior elicited by species specific stimuli provided by plumage and other characteristics of quail. Another set of experiments will be devoted to exploring how the subjects can become conditioned to respond sexually to arbitrary stimuli. In each set of experiments, different components of sexual behavior will be investigated separately. The research will address the following types of questions: How do males learn to approach and remain near females? What makes features of females effective in eliciting copulatory behavior? How do male subjects learn to discriminate between males and females? How do conditioned contextual cues influence sexual behavior?